Clockspring connector with carrier member

ABSTRACT

A clockspring connector is provided comprising a housing defining a chamber, including a carrier member having a first roller associated with a first turned-back loop of a first flat conductor cable and a second roller associated with a second turned-back loop of a second flat conductor cable wherein said first and second flat conductor cables are alternatingly coiled at an inner diameter of the chamber adjacent the hub or along said outer diameter of the chamber adjacent the housing wall. The clockspring connector includes a complaint roller member providing compression forces against the flat ribbon cable during rotation of the clockspring connector. A clockspring connector and method for producing the same is provided having a hub rotatably mounted within a housing, the housing defining a chamber, with an integrated carrier assembly mounted within the housing, the integrated carrier assembly having a frame with a first and second roller assembly, wherein the integrated carrier assembly includes a first and second flat ribbon cable each having a slack length that encircles and variably distributes within the housing, wherein a first and second conductive backbone is accessible to the first and second flat ribbon cable and the first backbone interconnects with the steering system to circle with the base upon rotation of the steering wheel, the first and second backbones being interconnected by the flat ribbon cables.

This application is a divisional of U.S. Ser. No. 09/107,108, filed Jun.30. 1998, which is a continuation-in-part of U.S. Ser. No. 08/986,866,filed Dec. 8, 1997, which is a continuation-in-part of U.S. Ser. No.08/667,634 filed Jun. 24, 1996, now U.S. Pat. No. 5,865,634, which is acontinuation of U.S. Ser. No. 08/276,954 filed Sep. 19, 1994, nowabandoned. The aforementioned parent applications are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

This invention pertains to a clockspring connector for enclosingelectrical conductor cables, the clockspring connector electricallyconnecting a rotatable electric device with a stationary electricdevice.

While the present invention may have multiple applications, the mostprevalent is for use in automobiles. An increasing number of automobileshave airbag crash systems. An airbag is typically located on thesteering wheel facing the driver. The airbag must be in continuouselectrical connection with sensors in the car body. The sensors providean electrical signal to the airbag crash assembly which instantlyinflates the airbag in the event of a crash. Accordingly, there is aneed for an electrical connection between the rotatable portion of theairbag assembly which is mounted to the steering wheel, and theremaining portion of the assembly which is in a stationary position inthe car body. Electrical connections between rotatable and stationaryparts are well known. Typically, an electrical brush rests upon aconductive ring, with one of the parts being rotatable to provide suchrotatable electrical connection. However, there is a risk, particularlyduring the impact of an accident, of a transient failure of electricalconnection with a brush and ring system which result in failure of theentire airbag system crash assembly.

Accordingly, a clockspring connector has previously been developed,comprising an outer housing, a rotor member and a multiple ofintermediate housing members for enclosing and connecting the members;the housing and rotor member rotatably associated with one another at aplurality of bearing surfaces. A "clockspring" is located inside theinterconnector. The clockspring of prior art devices includes a singleflat conductor cable having its ends conductively attached to conductorwires which pass out of the interconnector to unite the airbag to thesensing device. For example, U.S. Pat. No. 5,061,195 discloses aclockspring housing and assembly having a single flat conductor cabletherein.

It has also been known in the art to reduce the length of the flatconductor cable in order to reduce cost and needed space within theclockspring housing. For example, U.S. Pat. No. 5,277,604 incorporatesan assembly of at least eight rollers and turned-back portions of theflat conductor cable within the clockspring housing to decrease thelength of the flat cable and also prevent buckling and enhancereliability and smooth rotation of the clockspring connector. Such adesign requires a complex and expensive system of mounting the rollers.Such a design may be expensive and, as well, only accommodates a singleflat conductor cable.

The use of a pair of conductor cables was disclosed in U.S. Pat. No.3,763,455. The conductor cables were carried by an assembly of twentyspacers or rollers. This design also requires a multiplicity of parts,including numerous rollers which add to the assembly time and costs ofthe device.

As more controls are mounted on the steering wheel, more conductors arerequired to pass multiple electrical signals through the clockspringconnector. Prior art clocksprings have included conductor cables havingup to six conductors in each flat cable. The excess of six conductors islimited by the limited width of the flat conductor cable and theprocessing methods of manufacturing the flat cable. Accordingly, thereis needed a clockspring connector which can accommodate more than sixconductors.

Still further, assembling clocksprings is a laborious and costly processthat is prone to error. In particular, the known art requires that theclockspring be assembled from an assortment of components that guideflat ribbon cables in sync with the rotation of the steering wheel.Assembling the various components individually into a clockspring is atedious and labor intensive process. It is therefore an object of theinvention to provide for a clockspring that may readily be assembled andmanufactured.

It is still another object of the invention to provide for an integratedcarrier assembly having a frame and which easily assembles within asteering wheel.

It is another object of the present invention to provide a clockspringconnector having a minimal amount of moving parts.

It is a further object of the present invention to provide a clockspringconnector having flat conductor cable of minimal length.

It is another object of the present invention to provide a clockspringhaving a freely and independently rotating carrier member.

It is a further object of the present invention to provide a clockspringconnector that reduces vibration of the flat conductor cable by use of acompliant roller member.

SUMMARY OF THE INVENTION

The above objects and advantages are provided by a clockspring connectorcomprising a housing defining a chamber extending therethrough. Acarrier member positioned within the chamber having a complaint rollers.Flat conductor cable carried by the carrier member. The flat conductorcable having a first turned-back loop section associated with a firstroller and a second turned-back loop section associated with a secondroller. A first flat cable associated with the first roller and a secondflat cable associated with the second roller. A hub having an innerdiameter exit cavity for receiving the flat conductor cable. Whereuponrotation of the hub in a clockwise direction causes the first flatconductor cable to unwind from the hub and push against the carrier walladjacent the first roller and simultaneously the second flat cableunwinds off of the hub and pushes against the second wall of the carriermember adjacent the second roller causing the carrier member to rotatein a clockwise direction and to transfer the first and second flatcables from the hub to the outer diameter of the housing. Rotation ofthe hub in the counterclockwise direction causes the first flat cable topull on the first roller and the second flat cable to pull on the secondroller causing the first and second flat cables to unwind from the outerdiameter of the chamber and simultaneously causing the carrier member torotate in a counterclockwise direction.

A housing member receives the hub, the carrier member is mounted on thehub, and a cover encloses the carrier member and flat cables within thehousing. The cover having an outer diameter exit cavity.

In an alternative embodiment of the invention, the clockspring providesfor the housing to include an integrated carrier assembly rotatablymounted thereto. The housing itself includes a fixed cover and a basethat define a chamber. The integrated carrier assembly preferablycomprises a frame having one or more rollers that rotate independently.Within the housing, an inner diameter region is concentrically definedby a hub and the frame, and an outer diameter region is concentricallydefined by the frame and the housing. The first and second flat ribboncable are variably distributed to encircle the hub along either theinner or outer diameter regions. The flat ribbon cables pass andturn-back through the rollers of the frame, so that the portions of eachflat ribbon cables located in the inner and outer diameter regions movein opposite directions. Each flat ribbon cable includes a slack lengththat passes through a corresponding roller or roller pair to vary thedistribution of the flat ribbon cable between the inner and outerdiameter. The first and second flat ribbon cables interconnect to aninner backbone, as incorporated by previous embodiments, that isreceived by the base and accessible to each flat ribbon cable from theinner diameter region. An outer backbone is also accessible to each flatribbon cable along the outer diameter region, such that the flat ribboncables may interconnect the inner and outer backbone within theclockspring. In this way, rotation of the inner backbone causes the flatribbon cables to contact and rotate the integrated carrier assembly. Inparticular, the slack length of each flat ribbon cable may contact aroller and rotate the integrated carrier assembly in conjunction withthe intake or outtake of flat ribbon cable. Preferably, the slack lengthof each flat ribbon cable may contact one or the other roller forming aroller pair that receives each flat ribbon cable, thereby forcing theintegrated carrier assembly to rotate in either the clockwise orcounterclockwise direction.

These and other features of the invention are set forth below in thefollowing detailed description of the presently preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a clockspring connector;

FIG. 2 is a top view of a clockspring connector in a fully woundposition; and

FIG. 3 is a top view of clockspring connector in a fully unwoundposition;

FIG. 4 is a top view of an alternate embodiment of a clockspringconnector;

FIG. 5 is an enlarged view of a compliant roller member of FIG. 4;

FIG. 6 is a side cut-away view of the clockspring connector of FIG. 4taken at line 6--6; and

FIG. 7 is a top view of a clockspring embodiment of an alternativeintegrated carrier assembly in the unwound position.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

The clockspring connector of this invention is better understood byreferences to FIGS. 1-3 which show various aspects of a presentlypreferred clockspring connector. Turning to FIG. 1, a housing 10receives a hub 20. Mounted on the hub is a carrier member 30. A firstflat conductor cable 41 and a second flat conductor cable 42 is carriedby the carrier member 30. A cover 50 encloses the flat ribbon cables41,42, carrier member 30 and hub 20 within housing 10.

The housing 10 includes a ledge 12 upon which the base 22 of hub 20rests. The hub 20 and housing 10 are constructed of materials whichallow the hub 20 to freely rotate within the housing 10 and to reducethe amount of friction between the base 22 and ledge 12 to the greatestextent. Materials such as a teflon tape, silicon material or grease maybe inserted between the base 22 and ledge 12 in order to reduce frictionat these bearing surfaces and all other bearing surfaces of the presentinvention. An inner diameter exit cavity 24 protrudes downwardly fromthe base 22 of hub 20. Inserted within the inner diameter exit cavity 24is inner diameter backbone 26. The inner diameter backbone 26 receivesflat conductor cable at its entrance end 27 and insulated wires 28protrude from the exit end 29.

Mounted on the hub 20 and freely and independently rotatable thereon iscarrier member 30. The carrier member 30 is generally a sphericallyshaped member being molded of a thermoplastic polymer material in thepresently preferred embodiment. However, any material may be used toform the carrier member 30. The carrier member 30 includes a firstroller mounting area 37 and a second roller mounting area 38. Axles33,34 protrude upwardly from the roller mounting areas 37,38,respectively. Roller area walls 35,36 surround the roller areas 37,38and are correspondingly shaped to the outer diameter of first roller 31and second roller 32. Inner diameter corner 65 and outer diameter corner66 are located at each end of roller area walls 35,36. The totalcircumference of roller area walls 35,36 may be controlled by changingthe shape of corners 65,66 in order to control the path of the conductorcables 41,42. By rounding corners 65,66, the circumference of walls35,36 is reduced and the area which contacts the conductor cables 41,42is also reduced. By extending and bringing corners 65,66 to a point, thecircumference of walls 35,36 is increased which increases the surfacearea which contacts conductor cables 41,42.

First roller 31 is mounted on axle 33 and second roller 32 is mounted onaxle 34 of the carrier member 30. The first and second rollers 31,32rotate freely and independently on their axles 33,34. A multiplicity ofnubs 39a and 39b protrude from around the carrier member 30 toward thehub 20 or housing wall 15 and provide a surface against which theconductor cables 41,42 may rub and rotate against. The carrier member 30provides a member for mounting rollers 31,32 and separating theconductor cables 41,42 along the outer diameter of the chamber 14 fromthe conductor cables 41,42 at inner diameter of the chamber 14. Springmembers 62 are molded into the carrier member 30. Spacers 64 protrudefrom spring members 62 and help to keep the carrier member 30 positionedaxially within the clockspring housing chamber 14. The housing chamber14 is defined by the housing wall 15 around the circumference of thehousing 10. The chamber 14 is further defined by the hub base 22 at itsbottom and cover 50 at the top.

The present invention includes two flat conductor cables. A firstconductor cable 41 and second conductor cable 42 are adjacently coiledaround carrier member 30 within chamber 14 of the housing 10. The flatribbon cables 41,42 of a preferred embodiment of this invention areformed by laminating six conductors parallel to each other with a pairof insulating films one each side. The use of two flat ribbon cables41,42 having six conductors each provides for a total of twelveconductors carried by the preferred embodiment of this invention. It iswithin the scope of the present invention that more than two conductorcables could be carried by the present embodiment in order to increasethe number of conductors to an almost limitless combination. The firstconductor cable 41 includes first turned-back U-shaped loop section 43and second conductor cable 42 includes second turned-back U-shaped loopsection 44. First and second conductor cables 41,42 exit the clockspringat the outer diameter through the outer diameter exit cavity 52.Conductor cable tails 46 are folded perpendicularly to the path of theconductor cables within the chamber 14 and are received by the outerdiameter exit cavity 52. Outer diameter backbone 54 is received from theother end of the outer diameter exit cavity 52 from the conductor cabletails 46. Entrance cavity 56 of the outer diameter backbone 54 receivesthe first and second conductor cables 41,42. The conductors of thecables 41,42 are welded to the corresponding insulated wires 58 whichprotrude from the exit end 59 of outer diameter backbone 54.

Assembly of the clockspring connector having the hub 20 adjacent thehousing 10 occurs in order to allow for the easiest and quickestpossible assembly of the clockspring connector. While the hub 20includes the exit cavity 24 at the inner diameter, the hub 20 is therotatable member which is associated with the steering wheel of anautomobile. Rotation of the steering wheel of the automobilesimultaneously rotates the hub 20. The cover 50 having exit cavity 52 atits outer diameter is placed onto the housing 10 and is the stationarymember of the clockspring connector. The exit cavity 52 at the outerdiameter is associated with the steering column of an automobile and isstationary. Thus, although FIG. 1 shows assembly of the clockspringconnector having the inner diameter exit cavity 24 on the bottom and theouter diameter cavity 52 at the top of the assembly; when theclockspring connector is assembled to a steering assembly, it will beinverted so that the inner diameter exit cavity 24 and hub 20 are on thetop of the clockspring connector and the outer diameter exit cavity 52and cover 50 are on the bottom of the clockspring connector.

Operation of the clockspring can more easily be understood by viewingFIG. 2. The housing 10 has mounted therein carrier member 30 and hub 20.Mounted on the carrier member 30 is first roller 31 and second roller32. The clockspring connector is shown in the fully wound positionhaving the majority of the conductor cables 41,42 coiled around the hub20 at the inner diameter of the chamber 14. First roller 31 is mountedin roller area 37 on axle 33 of the carrier member 30. Second roller 32is mounted in second roller area 38 on axle 34 of the carrier member 30.First conductor cable 41 exits the outer diameter backbone 54 and coilsadjacent to the outer diameter wall 15 of the housing 10. Firstturned-back loop section 43 then coils around first roller 31 and thencoils around the hub 20. Second flat conductor cable 42 exits the outerdiameter backbone 52 and at second turned-back loop 44, coils aroundsecond roller 32 and then onto hub 20 from the opposite side, 180° fromthe position where the first conductor cable 41 coils onto the hub 20.First conductor cable 41' terminates at the inner diameter backbone 26,adjacent second flat conductor cable 42'.

The rotational movement of the steering wheel is transmitted to theclockspring connector through the hub 20 and inner diameter backbone 26.Rotation in the clockwise direction or in direction of arrows 70,71causes the first flat conductor cable 41 to unwind off of hub 20 andmove to the right at position 100 and rub against wall 35 of the firstroller area 37 of the carrier member 30. Simultaneously, second flatconductor cable 42 unwinds from hub 20 at point 102 and protrudes andrubs against wall 36 of second roller area 38 of carrier member 30. Asthe hub continues to unwind in the clockwise direction, the conductorcables 41,42 push against walls 35,36 and force the carrier member 30also to rotate clockwise. As the hub 20 and carrier member 30 rotateclockwise, the first flat conductor cable 41 is spooled out from firstroller 31 to completely encircle the outer diameter of the chamber 14adjacent the wall 15 of the housing 10. Simultaneously, the second flatconductor 42 is spooled out along second roller 32 at a position 180°from the first conductor cable 41, to provide a second coil layeredadjacently to the first conductor cable 41 at the outer diameter of thechamber 14. Rotation of the hub and carrier member 30 continue in theclockwise direction until the flat cables 41,42 are completely unwoundfrom the hub 10.

The completely unwound condition is shown in FIG. 3. Like numerals forlike elements of FIG. 2 are shown in FIG. 3. The clockspring connector 5is shown in a completely unwound position, i.e., the flat conductorcables 41,42 are not coiled around hub 20. To wind the clockspringconnector, the hub 20 is rotated in a counter-clockwise direction in thedirection in the direction of arrows 72,73. Upon rotation of the hub 20in a counter-clockwise direction, the first flat cable 41 pulls on thefirst roller 31 at first turned-back loop 43 causing the first roller 31to rotate. Simultaneously, second conductor cable 42 pulls on secondroller 32 at second turned-back loop 44 causing the second roller 32 torotate in clockwise direction. The pulling of the first cable 41 and thesecond cable 42 on the first and second rollers 31,32 causes the carriermember 30 to rotate in a counter-clockwise direction. As the hub 20 andcarrier member 30 continue to rotate counter-clockwise, the first andsecond conductors 41,42 are uncoiled from the outer diameter of thechamber 14 and become coiled again onto the hub 20. It can be seen thatin the completely unwound position, the coils are positioned along theouter diameter of the chamber 14 in a first layer 81, a second layer 82,a third layer 83, and a fourth layer 84. The first conductor cable 41and the second conductor cable 42 are alternatingly layered; whereinfirst layer 81 and third layer 83 are the first conductor cable 41 andthe second layer 82 and fourth layer 84 are the second conductor cable42. Upon the first rotation of the hub 20 in the counter-clockwisedirection, layer 81 is taken up from the outer diameter of the chamberonto the hub 20 by first roller 31. Simultaneously, second layer 82 istaken up by second roller 32. Upon a second rotation, third layer 83 istaken up by the continued rotation of first roller 31 in thecounter-clockwise direction and fourth layer 84 is taken up by secondroller 32. This alternating take-up sequence is correspondingly achievedalong the inner diameter of the chamber 14 by winding the clockspringconnector in the clockwise direction spooling first and second conductorcables 41,42 onto the hub 20.

Turning to FIG. 4 an alternate embodiment of the present invention isshown including a housing 110 having a hub 120. Mounted on the hub is acarrier member 130. A first flat conductor cable 141 is carried by thecarrier member 130. A cover encloses the carrier member and hub 120within the housing 110. The housing 110 is constructed of materialswhich allow the hub 120 to freely rotate within the housing 110 and toreduce the amount of friction between the base 122 of the housing 110.Material such as teflon tape, silicon material or grease may be insertedbetween the base 122 and the housing 110 in order to reduce the frictionat these bearing surfaces. As well, such materials may be used to reducefriction between the carrier member 130 and the housing 110. An innerdiameter exit area 126 receives the flat conductor cable 141 and thetape is attached to a backbone (not shown) which connects the flatconductor cable to external electrical wires.

The carrier member 130 is generally a spherically shaped member moldedof a thermoplastic polymer material in the presently preferredembodiment. However, any material may be used to form the carrier member130. The carrier member 130 includes a first roller mounting area 137and a second roller mounting area 187. In an embodiment the carriermember 130 may include six roller mounting areas and six roller members131. However, any number of roller mounting areas and rollers are withinthe scope of the present invention. Axles 133 protrude upwardly from theroller mounting area 137. Roller area walls 135, 136 surround the rollerareas 137 and are correspondingly cylindrically shaped to the outerdiameter of the roller member 131. The roller member 131 is mounted onaxle 133 and is retained on the axle by arm 160. In a preferredembodiment the arm 160 is integrally molded with the axle 133. The arm160 extends out from the axle beyond the inner-diameter of the rollermember 130. In a preferred embodiment the roller member 131 is formed ofa compliant material such as rubber or neoprene. The complaint materialallows the roller member 131 to maximize the compression forces that areapplied against the flat ribbon cable 141 holding the ribbon cable 141against the outer wall of the chamber 182 and the inner wall of thechamber 42. For example, a rubber O-ring manufactured by Apple RubberProducts, Inc. is used in an embodiment and has durometer measure of 70and a diameter of 19.5 mm and provides a compression force of 0.15 gramsagainst the flat ribbon cable 141 when the roller member is deformed byless than 20% of its original shape. The diameter of the roller member131 is approximately equal to the width of the chamber 182 ±.100 inch.The width of the chamber is defined by the shortest distance between theinner wall 152 and outer wall 151 of the housing 110.

In another embodiment the roller member 131 maybe formed of a lowfriction and rigid material at its inner diameter and a high frictionand compliant material along its outer diameter. The roller having amultiple composition provides for maximum friction against the flatribbon cable 141 while allowing for some compression. Having the rigidmaterial at the center of the roller member eliminates the possibilityof permanent deformation of the roller member. The roller member 131rotates freely and independently on the axle 133. The orientation ofmultiple roller members mounted on the carrier member 130 provides for acontinuous compression of the flat ribbon cable against the inner wall152 and outer wall 151 around the entire diameter of the clockspringhousing 110. The roller members 131 have an outer diameter approximatelyequal to the width between the inner wall 152 and outer wall 151. Theroller member 131 in the first roller area 137 also provides thefunction of a turn back loop in order to guide the flat ribbon cable 141in a U-shape from the hub 120 through the first roller area 137 andturning back to be guided along the outer wall 151. The embodiment shownin FIG. 4 discloses only a single flat ribbon cable 141. However, in analternative embodiment the present design may also incorporate multipleflat ribbon cables being carried by the carrier member 130 and theroller members 131.

The clockspring 110 in FIG. 4 is shown in the full counter-clockwiseposition having the flat ribbon cable 141 spooled onto the outer wall151 of the housing 110. As the hub 120 is rotated in a clockwisedirection the flat ribbon cable 141 moves through the first roller area137 and is coiled onto the inner wall 152 of the hub 120. As the flatribbon cable 141 moves from being coiled onto the outer wall 151 to theinner wall 152 the thickness of the coil tape on the outer wall 151 isreduced and the thickness of the coiled flat ribbon cable 141 on theinner wall 152 is increased. In other words the gap between the rollermember 131 and the inner and outer walls 151, 152 changes as the flatribbon cable 141 is spooled from the outer wall 151 to the inner wall152. Although the gap between the roller member 131 and the walls 151,152 varies, the compliant roller member 131 maintains a constantcompression against the flat ribbon cable 141, regardless of how manylayers of the coiled flat ribbon cable are located on either the outeror inner wall 151, 152. This procedure is reversed when the hub 120 isrotated in the counter-clockwise direction.

Turning to FIG. 5, an enlarged view of second roller area 187 is shown.The roller member 131 is mounted on axle 133 and is maintained thereonby arms 160, 161. The roller member 131 is mounted on carrier member 130which is mounted within the housing 110 of the clockspring between theouter wall 151 and inner wall 152. The flat ribbon cable 141 is shownhaving a first layer 191 and a second layer 192 coiled against the outerwall 151 of the housing 110. The two coiled layers 191 and 192 of theflat ribbon cable 141 cause the roller member 131 to compress and forman ovoid shape where the diameter of the roller member 131 where itcontacts the inner and outer walls 151, 152 is less than the diameter ofthe roller member 131 at points 201 and 202 where the roller member 131is adjacent the roller area walls 136, 137. The roller member 131 isalso offset toward the inner wall 152 so that the inner diameter of theroller member 131 forms a first gap 210 between the inner diameter ofthe roller member 131 and the axle 133 that is greater than a second gap211 formed between the inner diameter of the roller member and the axle133. In a preferred embodiment the roller member 131 includes an innerdiameter radius that is larger than the radius of the axle 133, so thatsuch an offset condition may be achieved. Consequently, when the hub isrotated and the flat ribbon cable 141 is coiled on the inner wall 152the roller member 131 will be offset in the other direction toward theouter wall 151 and the first gap 210 will be less than the second gap211. As well, the ovoid shape of the carrier member 131 will bemaintained in order to continue to provide compression of the rollermember 131 against the flat ribbon cable 141 coiled onto the inner wall152 of the housing 110. Therefore, it may be understood throughout theentire rotation of the hub and the winding and the unwinding of the flatribbon cable 141 a constant pressure will be applied against the flatribbon cable 141 compressing it against either the inner 152 or outer151 wall of the housing 110. This improved system provides for a quietclockspring operation which avoids vibrations of the flat ribbon cable141 that cause noise.

Turning to FIG. 6 a side elevation cut-away view of FIG. 4 taken at line6--6 is shown. The housing 110 is shown having hub 120 mounted thereonforming a cavity 182 in which the carrier member 130 is mounted. Rollermember 131 is mounted on axle 133 and maintained thereon by arms 161,162. As the clockspring is in its full counter-clockwise position,multiple layers of the flat ribbon cable 141 are coiled along outer wall151 and a single coil of the flat ribbon cable 145 is located alonginner wall 152 of the housing 110. In this orientation it can be seenthat the first gap 210 between the inner diameter of the roller member131 and the outer diameter of a first side 191 the axle 133 is greaterthan the second gap 211 on the opposed second side 192 of the axle 133.As discussed above, the roller member 131 being formed of a compliantmaterial provides for the roller member 131 providing a constantcompression force against the flat ribbon cable 141, 145 throughout theunwinding and winding of the flat ribbon cable onto the inner wall 151to the outer wall 151 of the clockspring housing 110.

It can be seen from the present invention that two flat conductor cablescan be easily wound with minimal components incorporated within theclockspring housing and with minimal length of flat conductor cable.

In still another preferred embodiment, FIG. 7 shows an integratedcarrier assembly 230 for employing rotatably mounted rollers to guideone or more flat ribbon cables. The integrated carrier assembly 230differs from previous embodiments in that it includes preassembledcomponents integrated as one unit for assembly purposes. As will bedescribed in greater detail, the integrated carrier assembly 230 of thepreferred embodiment includes a frame 260 with rollers or rollerassemblies mounted thereto. As with previous embodiments, the integratedcarrier assembly 230 resides with a chamber 214 defined by theclockspring housing 210. The preferred integrated carrier assembly 230includes a frame 260 having pairs of rollers for guiding the flat ribboncables thereto. In general, the integrated carrier assembly 230 operatesin similar fashion to previous clocksprings described herein.Accordingly, FIG. 7 shows that the integrated carrier assembly 230rotatably mounts to the hub 220, with the cover 250 fixedly mounted overthe housing 210 to enclose the hub 220 and integrated carrier assembly230. The housing 210 is also constructed of materials which allow thehub 220 to freely rotate therein in a manner that reduces frictionbetween the base (shown as numeral 22 in FIG. 1) and housing 210. Tothis end, materials such as Teflon tape, silicon material orconventional grease may be injected between the base 222 and the housing210. In similar fashion, the integrated carrier assembly 230 isrotatably secured to the housing 210 on the hub 220.

With further reference to FIG. 7, the frame 260 surrounds the hub 220and supports a plurality of rotatably attached rollers that maintain aguiding presence on the flat ribbon cables 240, 241. The frame 260 isoblong and contoured to extend across the chamber 214, with one or moreroller assemblies employing rollers that guide the flat ribbon cables240, 241. In the preferred embodiment, a first and second pair ofrollers 231, 231 and 232, 232 oppose one another across the frame 260,with each pair of rollers comprising two adjacent rollers. However, itshould be readily apparent to one skilled in the art that more or lessrollers may be used in similar or alternative arrangements. The rollersare rotatably secured to the frame 260 by corresponding first and secondconnector forks 238, 238 and 239, 239 that unitarily extend from theframe 260 and engage each roller 231 and 232 about the axle to allowfree rotation. For reference, an inner diameter region may be defined asthe concentric area between the integrated carrier assembly 230 and hub220, while the outer diameter region is defined as the concentric areabetween the housing 210 and integrated carrier assembly 230. The rollers231, 232 spool the flat ribbon cables 240, 241 from the inner diameterregion to the outer diameter region and thereback. Preferably, therollers comprise solid plastic, but may also include compliant rollersdiscussed elsewhere in this application may be substituted in thisembodiment.

As with previous embodiments, the flat ribbon cables 240, 241electrically connect two conductive backbones or conductive surfaceswithin the housing, where the first backbone is received by the base andis rotatable therewith to transmit the motion of the steering wheel. Forpurposes of this particular embodiment, the ribbon cables 240, 241connect the inner diameter backbone 226 with the outer diameter backbone254, in a manner described with previous embodiments herein. Each flatribbon cable 240, 241 is distributed to include a portion within theinner and outer diameters, where each flat ribbon may pass and turn-backthrough the roller assemblies 231, 232 to distribute their respectivelengths between the inner and outer diameters. In this way, when theflat ribbon cables 240, 241 distribute upon rotation of the innerbackbone 226, the portions of the respective flat ribbon cables 240, 241within the inner and outer diameter each move in opposite directionswith respect to one another. Each flat ribbon cable 240, 241 may alsohave a slack portion that is variable with rotation of the innerbackbone 226, and is defined approximately to be the cable lengthpositioned at any given moment between the rollers of each rollerassembly 231, 232. With rotation of the inner backbone 226, the flatribbon cables 240, 241 increasingly distribute between the inner orouter diameter region, depending on whether the clockspring is beingwound or unwound. FIG. 7 shows in greater detail one preferredconfiguration of the clockspring, with the flat ribbon cables 240, 241in the unwound position such that the amount of each flat ribbon cable240, 241 is maximized along the outer diameter region.

Since the arrangement of flat ribbon cables 240, 241 may equally beshared between the inner and outer diameter regions, the invention willbe described with reference to the wound position depicted in FIG. 7. Itshould be apparent to one skilled in the art that the distribution andmotion of the flat ribbon cable 240, 241 from the wound to the unwoundposition is substantially similar or equivalent to FIGS. 2 and 3 and theaccompanying text. This embodiment varies from previous embodiments byproviding an improved mechanism for guiding and supporting one or moreflat ribbon cables within the housing. Accordingly, FIG. 7 shows thateach flat ribbon cables 240, 241 may interconnect with the innerbackbone 226 to partially encircle the hub 220 along the inner diameter.Both flat ribbon cables 240, 241 interconnect with the inner backbone226, and extend to and encircle about the outer diameter from opposingends of the frame 260. As such, the flat ribbon cable 241 is shown to belonger than the other cable to provide for the extra length needed toencircle the hub 220 an extra 180 degrees.

As with previous embodiments, rotation of the steering wheel allows theinner backbone 226 to force the flat ribbon cables 240, 241 to variablydistribute among the inner or outer diameter regions. With respect tothe embodiment of FIG. 7, the steering wheel may be rotated in theclockwise direction to wind the flat ribbon cables 240, 241 about thehub 220. The winding motion forces the excess flat ribbon cables 240,241 through the respective pair of rollers 231, 231, and 232, 232. Ingeneral, each flat ribbon cable 240, 241 slackens as it passes throughthe respective rollers 231, 231 and 232, 232. The slack length in turnforcibly engages the roller pairs and thereby provides a reactive forcethat rotates the carrier member 230 in conjunction with the rotation ofthe inner backbone 226. In this way, the motion of the carrier member230 positions the rollers 231, 231, and 232, 232 to intake the flatribbon cable from the outer diameter region, so that the flat ribboncables 240, 241 cannot pinch or radially pull inwards with successiverotations of the inner backbone. In this way, the flat ribbon cables240, 241 may be fully wound from the unwound position about the hub 220,such that all excess cable resides in the inner diameter region.

It should be apparent to one skilled in the art that while the flatribbon cables 240, 241 are preferably slack when passing through therespective rollers 231, 232, a taught engagement between the rollers andflat ribbon cables 240, 241 is also contemplated. In a taughtengagement, each flat ribbon cable 240, 241 pulls one of the rollers inthe pair of rollers 231,232 as it passes from the outer to the innerdiameter region, with little excess slack forming between the rollers.The pulling motion of the flat ribbon cables 240, 241 through therollers 231 and 232 also causes the reactive force that rotates theintegrated carrier assembly 230 in conjunction with the intake of flatribbon cables.

Based on the configuration of FIG. 7, the flat ribbon cables 240, 241unwind from the inner diameter when the inner backbone 226 is rotated inthe counterclockwise direction. The counterclockwise rotation of theclockspring pushes the flat ribbon cables 240, 241 to unwind from theinside to the outside diameter regions. The unwinding rotation causesthe flat ribbon cables 240, 241 to slack while passing through rollers231, 231 and 232, 232. In turn, the pushing motion of the flat ribboncables 240, 241 causes the respective slack lengths to combine andforcibly contact the roller pairs and/or the integrated carrier assembly230, thereby rotating the integrated carrier assembly 230 in thecounterclockwise motion. In this way, the inner backbone 226 may berotated in the clockwise or counter clockwise direction to variablydistribute the excess length of each flat ribbon cable 240, 241 to andfrom the inner and outer diameter regions.

As with previous embodiments, this embodiment provides for the flatribbon cables 240, 241 to radially compress and reduce the slidingfriction that cause noise. However, this embodiment provides onesignificant improvement over the prior art in that it provides for theflat ribbon cables 240, 241 to compress only within the inner diameterregion. As such, this embodiment avoids the creation of folds andfracture points that tend to form when the flat ribbon cables arecomprised along the outer diameter region. More specifically, the flatribbon cables 240, 241 are confined within the small concentric spacebetween the frame 260 and hub 220, which allows the flat ribbon cables240, 241 to compress against one another and the frame/hub within theinner diameter region. In this manner, the invention reduces the amountof noise that often results from transferring the flat ribbon cables240, 241 between the inner and outer diameter regions.

A method of assembling the clockspring of this invention is alsoprovided for this embodiment. The method includes providing a housinghaving a fixed cover and a rotatable base, the housing receiving a firstand second conductive backbone, the first conductive backbone receivedby the base to be rotatable therewith and with the steering system. Inaddition, the method includes rotatably mounting the hub 220 to thehousing 210 to be freely rotatable with respect to the housing, androtatably mounting the integrated carrier assembly 230 to be freelyrotatable with respect to the hub 220 and the housing 210. The method offurther includes distributing the first flat ribbon cable 240 in thehousing 210 to interconnect the first and second backbone so that aportion of the first flat ribbon cable is distributed in the regionbetween the frame and the hub, and another portion of the flat ribboncable is distributed between the housing and the frame. The method mayalso include distributing a second flat ribbon cable 241 insubstantially similar fashion, and for compressing the first and secondflat ribbon cable 240, 241 against the hub with the frame 260. The flatribbon cables may be compressed by dimensioning the frame 260 withrespect to the hub 220 to provide for the inner diameter regiontherebetween to be sufficiently narrow to compress each flat ribboncable. Finally, the method of assembly may provide for securing theassembled clockspring to a steering system in a manner known andpracticed in the art.

While this embodiment preferably employs a design with two flat ribboncables, it should be readily apparent to one skilled in the art that theintegrated carrier assembly 230 may accommodate a single flat ribboncables design by providing only one pair of rollers. Likewise,additional roller pairs may be employed to incorporate three or moreflat ribbon cables in the clockspring. The use of more or less flatribbon cables is generally dictated by the number of closed circuitsrequired within the steering wheel, and not by limitations of thisinvention.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications may be madewithout departing from the spirit and scope of the present invention andwithout diminishing its attendant advantages. It is, therefore, intendedthat such changes and modifications be covered by the appended claims.

What is claimed is:
 1. A clockspring connector comprising:a clockspringhousing having an inner wall and an outer wall and a first and secondflat conductor cable coiled therebetween; a hub rotatably mounted withinsaid housing; a chamber defined by said housing and the chamber having awidth defined by the shortest distance between the inner and outer wall;and a carrier member mounted within said chamber having a plurality ofsubstantially annular roller members formed of a compliant materialhaving a diameter approximately equal to said width ±.100 inch, whereinthe roller members apply a compression force against the first andsecond flat conductor cables oriented on both the inner wall and theouter wall of the housing.
 2. The clockspring connector of claim 1wherein each of said roller members are formed from a rubber O-ring. 3.The clockspring connector of claim 1 wherein said carrier memberincludes at least four roller members mounted thereon, each formed of acompliant material.
 4. The clockspring connector of claim 1 wherein eachof said roller members includes a rigid material at its inner diameterand said compliant material at its outer diameter.
 5. The clockspringconnector of claim 1 wherein each of said roller members is mounted onan axle of said carrier member and an inner diameter of said rollermember is greater than an outer diameter of the axle wherein the rollermember may be offset from side to side on the axle during the coilingand uncoiling of the first and second flat conductor cables.
 6. Theclockspring connector of claim 5 wherein each of the roller member forma first gap between the inner diameter and the outer diameter on a firstside of the axle and a second gap between the inner diameter and theouter diameter on a second side of the axle so that the first gap islarger than the second gap when a majority of each flat conductor cableis coiled on the outer wall adjacent the second side of the axle and thesecond gap is larger than the first gap when a majority of each flatconductor cable is coiled on the inner wall adjacent the first side ofthe axle.
 7. The clockspring connector of claim 6 wherein a thickness ofeach of the flat conductor cables coiled on the inner wall variesproportionally to a width of the first gap.
 8. The clockspring connectorof claim 1 wherein:an inner diameter exit cavity receives a backbone;said backbone having an entrance end and an opposed exit end; saidentrance end receiving said first and second flat conductor cables; andsaid exit end having insulated wires extending therefrom.
 9. Theclockspring connector of claim 1 wherein:rotation of said hub from anunwound position causes said first and second flat conductor cables tobe wound from the outer diameter of said chamber, said first flatconductor cable passing through a first turned-back loop around one ofsaid roller members and wound onto said hub, said second flat conductorcable passing through a second turned-back loop around another of saidroller members and wound onto said hub; rotation of said hub from itswound position causes said first and second flat conductor cables to beunwound, said first conductor cable being unwound from said hub throughsaid first turned-back loop around one of said roller members to saidouter diameter of said chamber, said second conductor cable beingunwound from said hub through said second turned-back loop aroundanother one of said roller members to said outer diameter of saidchamber; and said roller members providing continuous compressionagainst said first and second flat conductor cables while each of theflat conductor cables is being wound and unwound from said hub.
 10. Theclockspring connector of claim 9 wherein said first and second flatconductor cables are coiled along said outer wall between said housingand said compliant roller members.
 11. The clockspring connector ofclaim 1 wherein:said hub is mounted upon a lip of said housing forming afirst side of said chamber;and a cover mounted on said housing defininga second side of said chamber.
 12. The clockspring connector of claim 1wherein said first and second flat conductor cables provide twelveconductors.
 13. The clockspring connector of claim 1 wherein:each ofsaid roller members is freely and independently rotatable from saidcarrier member.
 14. The clockspring connector of claim 1 wherein:saidcarrier member is freely and independently rotatable from said housingand said hub.